JP2014511146A5 - - Google Patents

Claims (10)

Crucible,
A silicon transfer system having a transfer point protruding above the crucible and including a feeder for transferring a controllable amount of silicon into the crucible;
A Czochralski growth system comprising: at least one doping mechanism for controllably delivering at least one dopant material to the silicon delivery system and thereby delivering the dopant material to the crucible.   The Czochralski growth system of claim 1, wherein the crucible includes an internal growth zone in fluid communication with an external delivery zone. The Czochralski growth system according to claim 2 , wherein the feeder conveys the silicon and dopant material into the external feeding zone of the crucible.   The Czochralski growth system of claim 1, wherein the system includes two doping mechanisms. A first doping mechanism controllably transports a first dopant material to the feeder, and a second doping mechanism controllably transports a second dopant material to the feeder, where the The Czochralski growth system according to claim 2 , wherein the first dopant material and the second dopant material are different. A method of Czochralski growth of a silicon ingot containing a dopant material at a concentration C having a segregation coefficient k, comprising:
i) providing a crucible having an internal growth zone in fluid communication with an external feed zone;
ii) pre-loading the ingrowth zone with silicon and the dopant material to form a mixture, wherein the mixture, when melted, has a concentration C / k of the dopant material;
iii) melting the mixture;
iv) initiating growth of the silicon ingot from the internal growth zone;
v) Conveying silicon and the dopant material feed into the external feed zone while growing the silicon ingot, the feed having an average concentration C of the dopant material when melted; ,
vi) removing the silicon ingot containing the dopant material at a concentration C. The method of claim 6 , further comprising pre-filling the external feed zone with silicon and the dopant material at a concentration C when molten prior to the step of initiating growth of the first silicon ingot. Method. The silicon ingot further includes a first dopant material having a segregation coefficient k ₁ at a concentration C ₁ and further comprising a second dopant material having a segregation coefficient k ₂ at a concentration C ₂ ;
Silicon, the first dopant material, and the second dopant material are pre-charged into the ingrowth zone to form a mixture, where the mixture, when melted, the first dopant material has a concentration _C 1 / _{k 1} and a concentration _C 2 / _{k 2} of the second dopant material,
Wherein the outer feed zone, silicon, to deliver the second dopant material of the first dopant material when it is melted concentrations C ₁ and when it is melted concentration C _2, The method of claim 6 . The method according to claim 6 , which is a continuous Czochralski growth method. A method of Czochralski growth of a silicon ingot containing a dopant material at a concentration C having a segregation coefficient k, comprising:
i) providing a crucible having an internal growth zone in fluid communication with an external feed zone;
ii) pre-loading silicon and the dopant material into the internal growth zone; iii) starting growth of the silicon ingot from the internal growth zone; and iv) in the internal growth zone, the silicon ingot Maintaining a first concentration of the dopant material in the silicon while growing;
v) maintaining a second concentration of the dopant material in silicon while growing the silicon ingot in the external delivery zone, wherein the second concentration is less than the first concentration. Including the steps.